Semiconductor optoelectronic devices such as laser diodes for optical transceivers can be efficiently fabricated using wafer processing techniques. Generally, wafer processing techniques simultaneously form a large number (e.g., thousands) of devices on a wafer. The wafer is then cut to separate individual chips. Simultaneous fabrication of a large number of chips keeps the cost per chip low, but each chip generally must be packaged and/or assembled into a system that protects the chip and provides both electrical and optical interfaces for use of the devices on the chip.
Assembly of a package or a system containing an optoelectronic device is often costly because of the need to align multiple optical components with a semiconductor device. For example, the transmitting side of an optical transceiver chip may include a Fabry Perot laser that emits an optical signal from an edge of the chip. However, a desired path of the optical signal may require light to emerge from another direction, e.g., the face of a package. A turning mirror can deflect the optical signal from its original direction to the desired direction. Additionally, a lens or other optical element may be necessary to focus or alter the optical signal and improve coupling of the optical signal into an external optical fiber. Alignment of a turning mirror to the edge of the chip, the lens to the turning mirror, and an optical fiber to the lens can be a time consuming/expensive process.
Wafer-level packaging is a promising technology for reducing the size and the cost of the packaging of optoelectronic devices. With wafer-level packaging, components that conventionally have been separately formed and attached are instead fabricated on a wafer that corresponds to multiple packages. The resulting structures can be attached either individually or simultaneously and later cut to separate individual packages.
Packaging techniques and structures that can reduce the size and/or cost of optoelectronic assemblies are sought.